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Calendar of Physics Talks Vienna
| CANCELLED: Stable blowup for wave maps and Yang-Mills models (Vienna Theory Lunch Seminar) |
| Speaker: | Matthias Ostermann (Universität Wien) |
| Abstract: | Unfortunately, the seminar has to be CANCELLED!
The wave maps equation first appeared in particle physics as a nonlinear sigma model and the Yang-Mills equations originated from gauge theory for the strong interaction. They constitute prototypes of nonlinear geometric wave equations which, remarkably, have an explicit solution that forms a singularity in finite time. To determine the significance of these blowup solutions for the underlying dynamics, one studies their stability. In this talk, we give an elementary introduction to the mathematical analysis of blowup in both model equations and present some new stability results.
[[part of the "Vienna Theory Lunch Seminar, see https://lunch-seminar.univie.ac.at ]] |
| Date: | Tue, 11.06.2024 |
| Time: | 12:30 |
| Duration: | 75 min |
| Location: | University of Vienna, Boltzmanngasse 5, 5th floor, Schrödinger Lecture Hall |
| Contact: | Florian Lindenbauer |
| Holography of Information in a Ball of Finite Radius |
| Speaker: | Nava Gaddam (International Centre for Theoretical Sciences, Bengaluru) |
| Abstract: | The principle of Holography of Information states that all information available in the bulk of spacetime is also available near its boundary at spatial infinity. However, physical observers never have access to spatial infinity. Therefore, we ask the question: "Is information contained in a ball of finite radius also holographic in nature?". Phrased differently, we ask whether correlation functions on the boundary of the ball capture all the information of all correlators in the bulk of the ball. In this talk, I will answer this question in the affirmative, within the confines of linearised quantum gravity coupled minimally to a free Klein-Gordon field, for generic low-energy states in asymptotically flat space. Interestingly, unlike at infinity, massive and massless fields can be captured within our framework. [...] |
| Date: | Tue, 11.06.2024 |
| Time: | 14:00 |
| Duration: | 60 min |
| Location: | Erwin Schrödinger-Hörsaal (Boltzmanngasse 5, 5th floor). |
| Contact: | Adrien Fiorucci, Ankit Aggarwal, Daniel Grumiller |
| Assembly and reactions of organic semiconductors on oxide thin film surfaces |
| Speaker: | Martin Sterrer (Universität Graz, Institute of Physics) |
| Abstract: | Tailoring the properties of molecules of the tetrapyrrole family (porphyrins, phthalocyanines) by metalation and functionalization is potentially useful for targeting specific applications, e.g., in the fields of catalysis, sensing, optoelectronics, and magnetism. To this end, on-surface preparation strategies, mostly carried out on metal surfaces, for variously functionalized porphyrins and phthalocyanines have been developed, that provided detailed insight into their hierarchical organization and allowed their structural, electronic, and chemical properties to be studied in detail. We have extended this approach to porphyrins and phthalocyanines deposited on ultrathin metal oxide films. In this talk, we will give an overview of our recent studies in this direction, which were specifically aimed at revealing the assembly, energy level alignment, and metalation of these molecules, as wel |
| Date: | Tue, 11.06.2024 |
| Time: | 16:00 |
| Location: | TU Wien, Institut für Angewandte Physik, E134 1040 Wien, Wiedner HauptstraÃe 8-10 Yellow Tower âBâ, 5th floor, SEM.R. DB gelb 05 B |
| Contact: | Prof. Dr. G. Parkinson |
| Exciting Quantum Systems Towards Exciting Spins with a Novel Technique in a SEM |
| Speaker: | Thomas Weigner (TU Wien Atominstitut) |
| Abstract: | Coherent electromagnetic radiation is generally used to excite or control quantum transitions. Inherently, this leads to a spatial resolution that is diffraction-limited. Our goal is to coherently couple the non-radiative near-field of an electron beam to a quantum system. By modulating the electron beam, we can generate an RF near-field. Exciting a quantum transition this way would not be diffraction-limited.
In this proof-of-principle experiment, we want to show that it is possible to excite electron spins in BDPA crystals by modulating the electron beam of a SEM. This novel approach has the potential to do high-resolution, in situ electron spin resonance analysis in an electron microscope.
In this talk, I will give you an overview of our experimental setup and highlight our recent efforts and current progress. In particular, I will talk about the sample preparation and the prospects o |
| Date: | Wed, 12.06.2024 |
| Time: | 16:15 |
| Duration: | 45 min |
| Location: | Helmut Rauch Lecture Hall |
| Contact: | Maximilian Prüfer |
| Creating and Exploring Bose-Einstein Condensates of Dipolar Molecules |
| Speaker: | Sebastian Will (Columbia University) |
| Abstract: | We have recently created the first Bose-Einstein condensate (BEC) of dipolar molecules [1-4]. We evaporatively cool sodium-cesium molecules from 700 nK to less than 10 nK, deep into the quantum degenerate regime. The lifetime of the molecular BEC is longer than one second, reaching a level of stability similar to ultracold atomic gases. A cornerstone of this advance is double microwave shielding, a novel technique that gives us control over intermolecular interactions and reduces inelastic loss of molecules by four orders of magnitude. The creation of a BEC constitutes the first observation of a phase transition in an ultracold molecular gas.
In this talk, I will discuss our experimental approach, share latest insights, and give an outlook on opportunities with our system for many-body quantum physics, quantum simulation and quantum information. Thanks to a large dipole moment, BECs of |
| Date: | Fri, 14.06.2024 |
| Time: | 10:00 |
| Duration: | 45 min |
| Location: | Helmut Rauch Hörsaal ATI |
| Contact: | Stephan Roschinski |
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